Ultrastructure of the Somatic and Buccal Cortex of the Tetrahymenine Hymenostome Glaucoma chattoni

SYNOPSIS The membranes, epiplasm, and fiber systems are described in the somatic cortex of Glaucoma chattoni strain HZ-1. Kinetodesmal fibers, postciliary and transverse microtubular ribbons, basal microtubules, transverse fibers and transverse accessory material are associated with kinetosomes. Longitudinal microtubular ribbons and mitochondria occur interkinetally. In the buccal cortex, the membranes, epiplasm and fibers of the 3 membranelles, the paroral kinety, the ribbed wall, and the cytostome are described. Comparisons between G. chattoni and other ciliates reveal ultrastructural differences of possible systematic significance. In the somatic cortex of this and other tetrahymenines. Iongitudinal microtubular ribbons and basal microtubules occur concurrently. In the buccal cortex, alveoli are absent in tetrahymenine membranelles. A table is presented of the fiber systems associated with single somatic kinetosomes of various ciliates whose cortical ultrastructure has been studied to date.     

Molecules and Morphologies: The Perpetuation of Pattern in the Ciliated Protozoa*†

SYNOPSIS. Three apparently conflicting generalizations concerning the relationships between molecules and cell structure may be derived from studies on cellular patterning in the ciliates. (A) Cells with identical genes and molecular composition may have different hereditary patterns. (B) Genes, through their prescribed molecular derivatives, constrain the modes of pattern permutation and define the states of greatest stability. (C) Cells with identical hereditary patterns may have entirely different genes and molecular compositions. These principles may be reconciled through the recognition that they are characteristically applicable over different time intervals. Hereditary differences within a clone and without related molecular differences (principle A) may persist for hundreds of cell generations, but they are resolved eventually within a constant environment (principle B) as the configuration of minimal free energy is approached. On an even longer time scale, molecular substitutions have occurred for many or most components of the cell, but these have been constrained by selective pressures on an ancient design (principle C) that disallow substitutions affecting certain form-function relations which have been elevated to an adaptive peak.     

Analysis of the proteins,glycoproteins and glycosaminoglycans of fibroblast adhesions to substratum

The focal adhesion preparations which remain attached to a glass substratum when fibroblast bodies are removed by a gentle stream of buffer have been analysed by gel electrophoresis coupled with other selective methods of analysis. The results are consistent with the presence of three classes of macromolecular components. (i) Muscle and associated proteins amongst which actin was abundant with significant amounts of tropomyosin, some myosin and traces of α-actinin. Some vimentin was present but no vinculin. We detected a major new protein component, as yet unidentified, with a molecular weight in the region of 50 000–55 000 which is not desmin or tubulin and could have an important function at the focal adhesion. (ii) Glycoproteins which are a specialised subset of those in the whole plasma membrane and included a family which bind ricin and therefore contain β-galactose end groups, together with a series having carbohydrate chains which bound neither ricin nor concanavalin A. The relative proportion of ricin-binding glycoproteins compared to concanavalin A-binding glycoproteins was higher than in whole plasma membranes. (iii) Glycosaminoglycans, with hyaluronate identified as the major component by column chromatography and its susceptibility to Streptomyces hyaluronidase.     

Ultrastructural observations on cortical granules in human follicular oocytes cultured in vitro

The fine structure, distribution, and fate of cortical granules in human oocytes cultured in vitro are reported. Follicular maturation in women with blocked Fallopian tubes was induced by clomiphene citrate and human chorionic gonadotropin, and preovulatory eggs were obtained by improved methods of laproscopy and oocyte recovery. These oocytes were then inseminated and cultured in a modified Ham's F10 medium for 3 to 72 hr to assess their fertilizability. Cortical granules were observed in all 17 unfertilized oocytes investigated, which had completed various stages of meiotic maturation. A marked increase in their numbers was observed in oocytes cultured for 3 to 6 hr. There was no evidence of spontaneous cortical granule release in any of the oocytes studied. It is concluded that cortical maturation expressed by proliferation of cortical granules is as significant a criterion as nuclear maturation in assessing maturity and fertilizability of oocytes cultured in vitro. A short sojourn in culture before insemination could improve chances of normal fertilization and embryo development, which has been recently achieved in our laboratory.     

TRACHELOMONAS HISPIDA VAR. CORONATA (EUGLENOPHYCEAE). I. ULTRASTRUCTURE OF CYTOSKELETAL AND FLAGELLAR SYSTEMS1,2

Trachelomonas hispida var. coronata Lemm. has a fibrous, mucilaginous, ovoid, mineralized envelope (lorica), the ornamentation and coloration of which are capricious in culture. Cells exhibit a radial distribution of most organelles: (i) A cortical endoplasmic reticulum, (ii) parietal chloroplasts, and (iii) a median vacuolar region surrounded by several Golgi bodies and diverse vesicles. Associated with the emergent flagellum is a “paraflagellar complex” that consists of dense globules, cross-striated ribbon-like structures, a paraflagellar body, and an array of parallel striated filaments. The stigma consists of a single layer of pigmented granules that partially surrounds the canal/reservoir transition zone where microtubular bands intersect. A microtubular cytoskeleton consists of pellicular microtubules, peri-canal microtubules, stigma-associated microtubules and para-reservoir microtubules. The thickenings on the posterior, concave margins of the pellicular strips suggest that this pellicle is of intermediate complexity between those of Euglena spirogyra (Ehrenb. and Trachelomonas volvocina (Ehrenb.).     

Higher medially-directed joint reaction forces are a characteristic of dysplastic hips: A comparative study using subject-specific musculoskeletal models

Acetabular dysplasia is a known cause of hip osteoarthritis. In addition to abnormal anatomy, changes in kinematics, joint reaction forces (JRFs), and muscle forces could cause tissue damage to the cartilage and labrum, and may contribute to pain and fatigue. The objective of this study was to compare lower extremity joint angles, moments, hip JRFs and muscle forces during gait between patients with symptomatic acetabular dysplasia and healthy controls. Marker trajectories and ground reaction forces were measured in 10 dysplasia patients and 10 typically developing control subjects. A musculoskeletal model was scaled in OpenSim to each subject and subject-specific hip joint centers were determined using reconstructions from CT images. Joint kinematics and moments were calculated using inverse kinematics and inverse dynamics, respectively. Muscle forces and hip JRFs were estimated with static optimization. Inter-group differences were tested for statistical significance (p ≤ 0.05) and large effect sizes (d ≥ 0.8). Results demonstrated that dysplasia patients had higher medially directed JRFs. Joint angles and moments were mostly similar between the groups, but large inter-group effect sizes suggested some restriction in range of motion by patients at the hip and ankle. Higher medially-directed JRFs and inter-group differences in hip muscle forces likely stem from lateralization of the hip joint center in dysplastic patients. Joint force differences, combined with reductions in range of motion at the hip and ankle may also indicate compensatory strategies by patients with dysplasia to maintain joint stability.     

A preliminary note on Incurvarioidea in New Zealand

Abstract

The Monotrysian superfamily Incurvarioidea (Lepidoptera) is now known to be present inNew Zealand. A mummified partly decayed male, parasitised pupae, larval head capsules, and characteristic cocoons are associated with long (1500–2000 mm) meandering cortical scribble-like mines in sapling Weinmannia, Nothofagus and Myrsine. The fragments and larval biology display features of Prodoxidae, but cannot be assigned to a genus.

Wing pattern, some forewing venation, pupal structure, male genitalia and some female ovipositor structures, larval head capsule and pronotum, and details of the pupal cell and larval mine are described and illustrated.     

Monostotic fibrous dysplasia in the temporal bone: A late prehistoric occurrence

Fibrous dysplasia, characterized by benign osteolytic and osteoblastic lesions may involve one or several bones. Recent investigators have suggested that it may be merely a phase of what have previously been thought to be several different bone disease. Isolated fibrous dysplasia in the temporal bone is infrequent. Several reports of this disease have appeared in the literature of paleopathology, but none involved only the temporal bone. Monostotic involvement of the right temporal bone was discovered in the skull of an adult male recovered from an archeological site dating from the Late Mississippian period (A. D. 1,350–A. D. 1,650). It will provide an opportunity for preliminary documentation of the antiquity of this disease in the southeastern portion of the United States.     

Two ANGUSTIFOLIA genes regulate gametophore and sporophyte development in Physcomitrella patens

In Arabidopsis thaliana the ANGUSTIFOLIA (AN) gene regulates the width of leaves by controlling the diffuse growth of leaf cells in the medio‐lateral direction. In the genome of the moss Physcomitrella patens, we found two normal ANs (PpAN1‐1 and 1‐2). Both PpAN1 genes complemented the A. thaliana an‐1 mutant phenotypes. An analysis of spatiotemporal promoter activity of each PpAN1 gene, using transgenic lines that contained each PpAN1‐promoter– uidA (GUS) gene, showed that both promoters are mainly active in the stems of haploid gametophores and in the middle to basal region of the young sporophyte that develops into the seta and foot. Analyses of the knockout lines for PpAN1‐1 and PpAN1‐2 genes suggested that these genes have partially redundant functions and regulate gametophore height by controlling diffuse cell growth in gametophore stems. In addition, the seta and foot were shorter and thicker in diploid sporophytes, suggesting that cell elongation was reduced in the longitudinal direction, whereas no defects were detected in tip‐growing protonemata. These results indicate that both PpAN1 genes in P. patens function in diffuse growth of the haploid and diploid generations but not in tip growth. To visualize microtubule distribution in gametophore cells of P. patens, transformed lines expressing P. patens α‐tubulin fused to sGFP were generated. Contrary to expectations, the orientation of microtubules in the tips of gametophores in the PpAN1‐1/1‐2 double‐knockout lines was unchanged. The relationships among diffuse cell growth, cortical microtubules and AN proteins are discussed.